Screw jack



May 15, 1923.

A. cLELAND SCREW JACK Filed` Sent. 22. 1921 mmua Patented May 15, 1923.

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ALEX CLELAND, OF NEW ORLEANS, LOUISIANA.

sonnw` JACK.

Application tiled,n September 22, 1921. i Serial 502,4 07Lv The invention relates to screw jacks par-k ticularly to that kind of jack known as a bottle jack, however the invention may be applied to any kind of jack, said invention having for. its object to provide the upper end of the feed screw with an annular ring disposed in a horizontal plane and provided with radially disposed pockets on two levels of said annular ring and having therein a plurality of ball bearings, said ball bearings engaging ball raceways of an annular plate which engages the article being raised or jacked.v said annular plate being provided with downwardly and inwardly extending detachable L-shaped lugs, the horizontal arms of which engage under the annular ring` and guide the plate in its pivotal action and prevent displacement of the plate.

lith the above and other objects in view the invention resides in the combination and arrangement of parts as hereinafter set forth, shown in the drawings, described and claimed, it being understood that changes in the precise embodiment of the invention may be made within the scope of what is claimed without departing from the spirit of the invention.

In the drawings Figure l is a side elevation of the jack, part of the upper end thereof being broken away to better show the structure.

Figure 2 is a top plan view of the jack part of the article engaging plate being broken away to show the radially disposed pockets for the reception of ball bearings in the annular ring carried by the upper end of the screw. j

Referring to the drawings, the numeral 1 designates a casing of a conventional form of bottle jack and 2 the handle carried thereby, by means of which handle the `jack may be moved from place to place and positioned as desired. Extending upwardly and slidable in a vertical disposed aperture 3 is a a conventional form of ratchet mechanism 5. Secured to the upper end of the screw 4l as at 6 is a sleeve 7, said sleeve being provided with radially disposed outwardly and upwardly extending arms 8, which merge into a horizontally disposed annular member. level or surface 10 higher than they surface 11 andvdisposed in said surfaces 10 and 11 andV in radial alignment with each other are pockets 10aL and 11a, in which pockets ball bearings 12 and 13 are disposed. Hereto fore considerable difliculty has been experiencedduring a jacking operation by the binding of the plate which engages` an article thereby increasing the power necessary to turn the ratchet mechanism 5. To

`overcome this diiiiculty a plate 14 is pro- The annular member 9 has an outer' vided'which plate on its under face is prof vided with ball raoeways 15 and 16. The ball raceway 15 receives the balls 12 and the race-way 16 receives the balls 13 thereby providing a double .ball bearing article engaging plate for the jack and eliminating the frictional engagement between the article which is being jacked and the jack to a minimum. Secured to the sides of the plate 14 at diametrically opposite points are downwardly extending arms 17, the horizontal portions 1S of which underlie the annular member 9 and prevent the plate le from displacement in relation to the annular member 9. The members 17 are detaohably secured by means of screws 19 to the plate .14,

thereby allowing the plate 14 to be easily and quickly removed for cleaning purposes.

The invention having been set forth what is claimed as new and useful is 1. The combination with a jack vhaving a movable screw, of an article engaging member carried by said screw. said member oomprising a pair of spaced annular members, one of said annular members being provided with radially disposed ball bearings disposed in radially disposed pockets of one of said annular members, the other annular member being provided with raceways engaging said ball bearings.

2. The combination with a jack having a movable screw, of an article engaging member carried by said screw, said article engaging member comprising spaced annular members, one of said annular members being carried by the end of the screw, radially disposed ball bearings disposed in radially disposed pockets on two levels ofthe screw Carried annular members, the second annular member being provided with raeeways engagno' the balls on botl. of the levels of the screw Carried annular member, diametroally disposed detachable members carried by the upper annular member and extending downwardly and terminating in horizotally disposed arms engaging the under face of the screw earrled annular member.

In testimony whereof I have signed my name to this specification 1n the presence of 10 two subscribing Wltnesses.

ALEX CLELAND.

Witnesses DANIEL T. SITTooN, Jr., BIRDIE E. OCONNOR. 

